1. Field of the Invention
The present invention pertains to apparatus for loading drums or barrels, empty or loaded with product, onto pallets for further handling. More specifically, the present invention pertains to apparatus for engaging and lifting one or more drums from a predetermined loading position and transferring and lowering he drums onto pallets for further handling.
2. Description of the Prior Art
Many products are placed in drums or barrels for shipment or use. For ease of handling, such drums, empty or filled, are typically placed in multiples, e.g. four drums, in upright positions on a pallet made of wood or other suitable material. As such, the drums are more easily handled, with forklifts or the like, and shipped by truck, train, ship, etc. A number of automatic or semi-automatic drum pelletizing devices have been developed for this purpose.
In most drum pelletizing apparatus of the prior art, individual drums are carried by a conveyor to some predetermined loading position at or near the drum pelletizing apparatus. The drums are then engaged in some manner, individually, in pairs, or other multiples, and lifted or pushed from the predetermined loading position onto an empty pallet which has been positioned to receive them. After the pallet is loaded, the pallet and drums loaded thereon are transferred, perhaps by another conveyor, to another area for further handling. Several pelletizing devices are disclosed in U.S. Pat. Nos. 3,402,831; 3,831,782 and 4,632,633.
In some of these prior art devices, the drums are placed in a tilted, off-center position and then tilted upright onto a pallet. In at least one other, a grappling device is provided for engaging the upper rim of a drum or barrel for lifting the drum and transferring it onto a pallet. If a drum is not completely lifted, it must be tilted, rolled or shoved across a pallet to its ultimate loading position. In doing so, pallets and drums are frequently damaged. In fact, a drum may be penetrated causing its contents to spill. In other devices in which the drums are completely lifted before transfer to a pallet, such as the previously mentioned grappling device, loads may be so concentrated as to cause damage and possible spillage of drum contents. %n any of these cases, automatic operation will be interrupted for clean up and/or repair. In the case of hazardous materials, personnel and environment may be subjected to inherent dangers. Furthermore, certain types of drums, such as plastic or wood, may not be suitable for lifting by some of the drum palletizers of the prior art.
While there are a number of palletizer designs, many have inherent problems. Others have been designed for very specific purposes. Improvements continue to be sought.